Anthropic's text watermark is easy to bypass on several older Claude models Matthias Bastian View the LinkedIn Profile of Matthias Bastian Nov 4, 2026 Nano Banana Pro prompted by THE DECODER Ask about this article… Search Update, November 4, 2026: Anthropic emailed API customers again about a second round of watermark retrofits. Starting November 16, 2026, Claude Opus 4.6, Claude Opus 4.5, Claude Sonnet 4.5, and Claude Haiku 4.5 will all get text watermark